Comparing ArrayList elements with Hash map Keys

Posted on 2009-07-01
Last Modified: 2013-12-22
I have a arraylist and hash map .
I want wen ever there is matching in arraylst elemtns and hashmap keys
corresponding vales sud be put in a new list.
The values of HashMap is list.
My given codeis failing somewhere between.
Please check..
import java.text.DecimalFormat;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.HashMap;

import java.util.HashSet;

import java.util.Iterator;

import java.util.List;

import java.util.Map;

import java.util.Set;

public class test5


	public ArrayList<String> getData(HashMap<String, ArrayList<String>> AMap,ArrayList<String> temp)



		System.out.println(" Invloking getData ");

		Set<String> tempSet = new HashSet<String>(temp);

        System.out.println("getData "+tempSet);

        Set commonKeys = new HashSet(AMap.keySet());

        ArrayList<String> ruleGroupIds = new ArrayList<String>(commonKeys);

        commonKeys.retainAll( tempSet );


	 	for (Object key : commonKeys) 


		      ArrayList<String>  value = (ArrayList<String>) AMap.get(key);



	 	System.out.println("result " + ruleGroupIds);

 	    return ruleGroupIds;


	public static void main(String args[])


		ArrayList<String> compareList = new ArrayList<String>();

		compareList.add("A");	compareList.add("B");	compareList.add("D");

		ArrayList<String> superList = new ArrayList<String>();

		ArrayList<String> ruleGroupIds = new ArrayList<String>();

		ArrayList<String> ruleGroupIdsss = new ArrayList<String>();



		HashMap<String, ArrayList<String>> hm = new HashMap<String, ArrayList<String>>();




		test5 t = new test5();

		t.getData(hm, compareList);



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Question by:satyabrata25
1 Comment

Accepted Solution

serrutom earned 250 total points
Comment Utility

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import java.util.Set;

public class Test5 {

	public static void main(String args[]) {

		ArrayList<String> listA = new ArrayList<String>();




		HashMap<String, String> listB = new HashMap<String, String>();

		listB.put("A", "Test A");

		listB.put("B", "Test B");

		listB.put("C", "Test C");

		listB.put("D", "Test D");

		listB.put("E", "Test E");

		Test5 t = new Test5();

		List<String> newList = new ArrayList();

		Set<String> keys = listB.keySet();

		for (String key : keys) {

			if(listA.contains(key)) {





		for(String s : newList) {





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